diff --git a/hub/internal/service/connection_manager/agent_test.go b/hub/internal/service/connection_manager/agent_test.go
index 2f3bc3c..e1cad49 100644
--- a/hub/internal/service/connection_manager/agent_test.go
+++ b/hub/internal/service/connection_manager/agent_test.go
@@ -3,7 +3,6 @@ package connection_manager
 import (
 	"context"
 	"errors"
-	"io"
 	"sync"
 	"testing"
 	"time"
@@ -14,108 +13,6 @@ import (
 	"gotest.tools/v3/assert"
 )
 
-type streamMock struct {
-	recvCh    chan *pb.AgentEvent
-	sendCh    chan *pb.ServerCommandRequest
-	closeCh   chan struct{}
-	ctx       context.Context
-	mu        sync.Mutex
-	sendErr   error
-	recvErr   error
-	closeOnce sync.Once
-}
-
-func (f *streamMock) Context() context.Context {
-	return f.ctx
-}
-
-func (f *streamMock) Send(request *pb.ServerCommandRequest) error {
-	f.mu.Lock()
-	err := f.sendErr
-	f.mu.Unlock()
-	if err != nil {
-		return err
-	}
-	f.sendCh <- request
-	return nil
-}
-
-func (f *streamMock) Recv() (*pb.AgentEvent, error) {
-	f.mu.Lock()
-	recvErr := f.recvErr
-	f.mu.Unlock()
-	if recvErr != nil {
-		return nil, recvErr
-	}
-	select {
-	case msg, ok := <-f.recvCh:
-		if !ok {
-			return nil, io.EOF
-		}
-		return msg, nil
-	case <-f.ctx.Done():
-		return nil, f.ctx.Err()
-	}
-}
-
-func (f *streamMock) Close() error {
-	select {
-	case f.closeCh <- struct{}{}:
-	default:
-	}
-	f.closeOnce.Do(func() {
-		close(f.recvCh)
-	})
-	return nil
-}
-
-type heartBeatMock struct {
-	mu       sync.Mutex
-	countUse int
-	doneCh   chan struct{}
-	err      error
-}
-
-func (h *heartBeatMock) CreateHeartbeat(ctx context.Context, heartbeat domainHub.CreateHeartbeatModel) error {
-	h.mu.Lock()
-	h.countUse += 1
-	err := h.err
-	h.mu.Unlock()
-	select {
-	case h.doneCh <- struct{}{}:
-	default:
-	}
-	return err
-}
-
-type statusMock struct {
-	mu     sync.Mutex
-	online bool
-	doneCh chan struct{}
-}
-
-func (s *statusMock) Offline() {
-	s.mu.Lock()
-	s.online = false
-	s.mu.Unlock()
-}
-
-func (s *statusMock) Online() {
-	s.mu.Lock()
-	s.online = true
-	s.mu.Unlock()
-	select {
-	case s.doneCh <- struct{}{}:
-	default:
-	}
-}
-
-func (s *statusMock) IsOnline() bool {
-	s.mu.Lock()
-	defer s.mu.Unlock()
-	return s.online
-}
-
 type agentTestHarness struct {
 	ctx       context.Context
 	cancel    context.CancelFunc
diff --git a/hub/internal/service/connection_manager/manager.go b/hub/internal/service/connection_manager/manager.go
index baacfd6..acd4159 100644
--- a/hub/internal/service/connection_manager/manager.go
+++ b/hub/internal/service/connection_manager/manager.go
@@ -21,11 +21,11 @@ func NewConnectionManager(heartbeat heartbeatStore, status statusNotifier, logge
 	return &ConnectionManager{heartbeat: heartbeat, log: logger, status: status, agentConnStore: NewAgentConnStore()}
 }
 
-func (c *ConnectionManager) NewConnection(stream streamConn) {
+func (c *ConnectionManager) NewConnection(stream streamConn) error {
 	AgentID, err := agentIDFromMetadata(stream.Context())
 	if err != nil {
 		c.log.Error().Err(err).Msg("missing agent id in metadata")
-		return
+		return fmt.Errorf("get agent id: %w", err)
 	}
 	c.log.Info().Str("agentID", AgentID).Msg("connection accepted")
 
@@ -41,6 +41,8 @@ func (c *ConnectionManager) NewConnection(stream streamConn) {
 		}
 		c.agentConnStore.Delete(AgentID)
 	}()
+
+	return nil
 }
 
 func (c *ConnectionManager) GetConnection(AgentID string) (*AgentConnection, error) {
diff --git a/hub/internal/service/connection_manager/manager_test.go b/hub/internal/service/connection_manager/manager_test.go
index dc1ee8e..3bd443d 100644
--- a/hub/internal/service/connection_manager/manager_test.go
+++ b/hub/internal/service/connection_manager/manager_test.go
@@ -1 +1,110 @@
 package connection_manager
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	pb "github.com/lorsanstand/HomeOps-Hub/api/gen/homeops"
+	"github.com/rs/zerolog"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc/metadata"
+	"gotest.tools/v3/assert"
+)
+
+type connectionManagerTestHarness struct {
+	heartbeat *heartBeatMock
+	status    *statusNotifierMock
+	manager   *ConnectionManager
+}
+
+func newConnectionManagerTestHarness(t *testing.T) *connectionManagerTestHarness {
+	t.Helper()
+
+	heartbeat := &heartBeatMock{doneCh: make(chan struct{}, 2)}
+	status := &statusNotifierMock{agentIDCh: make(chan string, 1)}
+
+	manager := NewConnectionManager(heartbeat, status, zerolog.New(nil))
+
+	return &connectionManagerTestHarness{manager: manager, status: status, heartbeat: heartbeat}
+}
+
+func newMetadataAgentID(t *testing.T, agentID string) metadata.MD {
+	t.Helper()
+
+	return metadata.New(map[string]string{"agent-id": agentID})
+}
+
+func TestNewConnectionManager_NewConnection(t *testing.T) {
+	h := newConnectionManagerTestHarness(t)
+	agentID := "123"
+
+	ctx := metadata.NewIncomingContext(context.Background(), newMetadataAgentID(t, agentID))
+
+	stream := streamMock{ctx: ctx,
+		recvCh:  make(chan *pb.AgentEvent, 1),
+		sendCh:  make(chan *pb.ServerCommandRequest, 1),
+		closeCh: make(chan struct{}, 1),
+	}
+
+	err := h.manager.NewConnection(&stream)
+	assert.NilError(t, err)
+
+	select {
+	case ID := <-h.status.agentIDCh:
+		require.Equal(t, agentID, ID)
+	case <-time.After(200 * time.Millisecond):
+		t.Fatalf("get agent id for notifier")
+	}
+
+	agentIDs := h.manager.GetAllAgentID()
+	assert.Equal(t, agentID, agentIDs[0])
+
+	agent, err := h.manager.GetConnection(agentID)
+	assert.NilError(t, err)
+	require.NotNil(t, agent)
+
+}
+
+func TestNewConnectionManager_NewConnectionNotAgentID(t *testing.T) {
+	h := newConnectionManagerTestHarness(t)
+
+	stream := streamMock{ctx: context.Background(),
+		recvCh:  make(chan *pb.AgentEvent, 1),
+		sendCh:  make(chan *pb.ServerCommandRequest, 1),
+		closeCh: make(chan struct{}, 1),
+	}
+
+	err := h.manager.NewConnection(&stream)
+	assert.ErrorContains(t, err, "get agent id")
+}
+
+func TestNewConnectionManager_AgentNotFound(t *testing.T) {
+	h := newConnectionManagerTestHarness(t)
+	_, err := h.manager.GetConnection("123")
+	assert.ErrorIs(t, ErrNotFoundConn, err)
+
+	agentIDs := h.manager.GetAllAgentID()
+	assert.Equal(t, len(agentIDs), 0)
+}
+
+func Test_agentIDFromMetadata(t *testing.T) {
+	agentID := "123"
+
+	ctx := metadata.NewIncomingContext(context.Background(), newMetadataAgentID(t, agentID))
+	id, err := agentIDFromMetadata(ctx)
+	assert.NilError(t, err)
+	assert.Equal(t, id, agentID)
+}
+
+func Test_agentIDFromMetadata_MetadataNotFound(t *testing.T) {
+	ctx := context.Background()
+	_, err := agentIDFromMetadata(ctx)
+	assert.ErrorContains(t, err, "metadata not found")
+}
+
+func Test_agentIDFromMetadata_AgentIDNotFound(t *testing.T) {
+	ctx := metadata.NewIncomingContext(context.Background(), newMetadataAgentID(t, ""))
+	_, err := agentIDFromMetadata(ctx)
+	assert.ErrorContains(t, err, "agent-id not found")
+}
diff --git a/hub/internal/service/connection_manager/mock_test.go b/hub/internal/service/connection_manager/mock_test.go
new file mode 100644
index 0000000..881eb5b
--- /dev/null
+++ b/hub/internal/service/connection_manager/mock_test.go
@@ -0,0 +1,125 @@
+package connection_manager
+
+import (
+	"context"
+	"io"
+	"sync"
+
+	pb "github.com/lorsanstand/HomeOps-Hub/api/gen/homeops"
+	domainHub "github.com/lorsanstand/HomeOps-Hub/hub/internal/domain"
+)
+
+type streamMock struct {
+	recvCh    chan *pb.AgentEvent
+	sendCh    chan *pb.ServerCommandRequest
+	closeCh   chan struct{}
+	ctx       context.Context
+	mu        sync.Mutex
+	sendErr   error
+	recvErr   error
+	closeOnce sync.Once
+}
+
+func (f *streamMock) Context() context.Context {
+	return f.ctx
+}
+
+func (f *streamMock) Send(request *pb.ServerCommandRequest) error {
+	f.mu.Lock()
+	err := f.sendErr
+	f.mu.Unlock()
+	if err != nil {
+		return err
+	}
+	f.sendCh <- request
+	return nil
+}
+
+func (f *streamMock) Recv() (*pb.AgentEvent, error) {
+	f.mu.Lock()
+	recvErr := f.recvErr
+	f.mu.Unlock()
+	if recvErr != nil {
+		return nil, recvErr
+	}
+	select {
+	case msg, ok := <-f.recvCh:
+		if !ok {
+			return nil, io.EOF
+		}
+		return msg, nil
+	case <-f.ctx.Done():
+		return nil, f.ctx.Err()
+	}
+}
+
+func (f *streamMock) Close() error {
+	select {
+	case f.closeCh <- struct{}{}:
+	default:
+	}
+	f.closeOnce.Do(func() {
+		close(f.recvCh)
+	})
+	return nil
+}
+
+type heartBeatMock struct {
+	mu       sync.Mutex
+	countUse int
+	doneCh   chan struct{}
+	err      error
+}
+
+func (h *heartBeatMock) CreateHeartbeat(ctx context.Context, heartbeat domainHub.CreateHeartbeatModel) error {
+	h.mu.Lock()
+	h.countUse += 1
+	err := h.err
+	h.mu.Unlock()
+	select {
+	case h.doneCh <- struct{}{}:
+	default:
+	}
+	return err
+}
+
+type statusMock struct {
+	mu     sync.Mutex
+	online bool
+	doneCh chan struct{}
+}
+
+func (s *statusMock) Offline() {
+	s.mu.Lock()
+	s.online = false
+	s.mu.Unlock()
+}
+
+func (s *statusMock) Online() {
+	s.mu.Lock()
+	s.online = true
+	s.mu.Unlock()
+	select {
+	case s.doneCh <- struct{}{}:
+	default:
+	}
+}
+
+func (s *statusMock) IsOnline() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.online
+}
+
+type statusNotifierMock struct {
+	agentIDCh chan string
+}
+
+func (s *statusNotifierMock) New(AgentID string) statusAgent {
+	select {
+	case s.agentIDCh <- AgentID:
+	default:
+
+	}
+	return &statusMock{doneCh: make(chan struct{}, 2)}
+}